dlg2html is a set of Bash shell scripts which help automate the
conversion of DLG Pro message bases to HTML for archiving or mirroring
on the Web. (DLG Pro is a Bulletin Board System for Amiga personal
computers.) The HTML message files contain the appropriate links to the
next and previous messages, as well as to any replies or referenced
messages. A message index is also produced. dlg2html works with terminal
dumps of DLG message boards, which means that you do not need access to
the actual BBS files to perform the conversion.

FUDforum is a templatable forum with i18n support based on PHP and either MySQL, Oracle, PostgreSQL, or SQLite. It features a user/group management system, a multi-lingual spell checker, both flat and thread message views, a private messaging system with multi-user forwarding capabilities, poll file attachments, and much more. It is an extremely fast and scalable forum that can fulfil the needs of both small and large forum operators.

TinyIB is a lightweight PHP image board which emulates the functionality of 4chan. If you use MySQL or SQLite, you can use it to create an efficient setup able to handle large amounts of traffic. If you don't use a database, it can store posts as text files for a portable setup capable of running on virtually any PHP host.

Sukiyaki was born out of what the author sees as a much needed improvement to current imageboard/BBS software. They're flaky, often have security flaws that users take advantage of, and worst of all, they have the same UI from the mid-nineties. It's time for an update!
Sukiyaki visually organizes replies in threads so that it is clear who the reply is sent to. It is written using Django with its wonderful ORM, which helps reduce security vulnerabilities. It has been tested in production and is stable. It also includes a unique system for user-ranking of posts. Planned features include RSS updates for individual boards and threads, and there is a faster backend (Django-Treebeard).

Kusaba X is a continuation of the Kusaba image board project. It allows you to make your own image board, similar to 2channel and 4chan. Unlike a lot of other image board software, it allows you to set up multiple boards and control them from one centralized management panel.